Whole foods tend to be loaded with nutrients. In general, getting your nutrients from foods is better than getting them from supplements. That being said, some foods are much more nutritious than others. In some cases, one serving of a food can satisfy more than 100% of your daily requirements for one or more nutrients.

It is one of the most nutrient-dense foods on the planet, and is particularly high in vitamin K1.

Vitamin K1 is essential for blood clotting and may play a role in bone health.

One cup, or 67 grams, of fresh kale contains the following nutrients in extremely high amounts:

Vitamin K1: 900% of the RDI.

Vitamin C: 134% of the RDI.

Copper: 111% of the RDI.

Furthermore, kale is also high in fiber, manganese, vitamin B6, potassium and iron.Bottom Line: Kale contains very high amounts of vitamin K1, vitamin C and copper. A single serving of fresh kale provides over 100% of the recommended daily intake (RDI) for these nutrients.

2. Seaweed

Iodine deficiency is one of the most common nutrient deficiencies in the world, affecting nearly one-third of the global population.

Iodine deficiency causes thyroid problems in adults. During pregnancy, it may also increase the risk of mental retardation and developmental abnormalities in the unborn child.

Seaweed — such as kelp, nori, kombu and wakame — are all very rich in iodine.

The recommended daily intake is 150 micrograms/day. However, different types of seaweed contain varying amounts of iodine:

Wakame: 1 g has about 30–110 micrograms, which is close to the RDI.

Kelp: 1 g may have 700–1500 micrograms, or 460–1000% of the RDI.

Occasional seaweed consumption is a cheap, effective way to prevent iodine deficiency.

However, some types of seaweed, such as kelp, should not be consumed daily. Just one gram may exceed the upper level of safe intake, which is 1100 micrograms per day. This may cause adverse effects.Bottom Line: Seaweed is an excellent source of iodine, as one gram provides 20-1000% of the RDI. However, kelp is much higher in iodine than other types of seaweed, and should not be consumed daily.

3. Liver

The liver is the most nutritious part of any animal.

It is rich in essential nutrients, including vitamin B12, vitamin A, iron, folate and copper.

Vitamin B12 intake is particularly important, as many people are lacking in it. It plays a crucial role in cell, brain and nervous system health.

Beef liver contains high amounts of vitamin B12, vitamin A and copper. A 100-gram (3.5 oz) serving may contain the following quantities of these nutrients:

Vitamin B12: 1200% of the RDI.

Vitamin A: 6–700% of the RDI.

Copper: 6–700% of the RDI.

Just be sure not to eat liver more often than once or twice a week, because excessive buildup of these nutrients may occur.Bottom Line: Liver contains very high amounts of vitamin B12, vitamin A and copper. However, it should not be consumed more than once or twice a week.

4. Brazil Nuts

If you are lacking in selenium, then Brazil nuts may be the perfect snack.

Selenium is essential for human health. It is necessary for thyroid and immune system function, as well as antioxidant activity.

The recommended daily amount is 50–70 micrograms, which may be achieved by consuming just one large Brazil nut.

Each nut may provide up to 95 micrograms of selenium.

The upper tolerance level for selenium is set at about 3–400 micrograms per day for adults, so make sure not to eat too many of them.Bottom Line: Brazil nuts are the single best dietary source of selenium. Just one large nut contains more than the recommended daily amount.

5. Shellfish

Shellfish, such as clams and oysters, are among the most nutritious types of seafood.

Clams are packed with vitamin B12. In fact, 100 grams provide over 1600% of the RDI.

Furthermore, they contain high amounts of other B-vitamins, potassium, selenium and iron.

Oysters are another type of nutritious shellfish. They contain an abundance of zinc and vitamin B12, with 100 grams containing 2–600% of the RDI.

Clams and oysters may be the perfect food for older individuals, as higher amounts of vitamin B12 are recommended after the age of 50.

This is because the ability to absorb vitamin B12 in the digestive system may decrease with age.

Bottom Line: Clams and oysters both contain high amounts of vitamin B12, which is very important for older individuals. Shellfish are also high in many other nutrients.

6. Sardines

Sardines are small, oily and nutrient-rich fish.

Although they are commonly served in cans, sardines can also be grilled, smoked or pickled when fresh.

Sardines are very rich in EPA and DHA, essential omega-3 fatty acids that have been linked with improved heart health.

One 92-gram (3.75 oz) serving contains more than half of the RDI for these essential fatty acids. It also contains over 300% of the RDI for vitamin B12.

Furthermore, sardines contain a little bit of almost every nutrient we need, including high amounts of selenium and calcium.

Bottom Line: Sardines are a very nutrient-rich fish. They contain high

7. Yellow Bell Peppers

Yellow bell peppers are one of the best dietary sources of vitamin C.

Vitamin C is an essential vitamin. It is also water-soluble, meaning that extra amounts do not get stored in the body. Therefore, having a regular supply of vitamin C in the diet is very important.

Vitamin C deficiency, also known as scurvy, is very rare these days. Symptoms include fatigue, skin rashes, muscle pain and bleeding disorders.

High vitamin C intake has been linked with enhanced immune function, a reduced risk of DNA damage and a decreased risk of several chronic diseases.

One large yellow bell pepper, or about 186 grams, provides almost 600% of the recommended daily intake of vitamin C, which is 75–90 mg.
For comparison, yellow bell peppers contain about 3–4 times the amount of vitamin C found in oranges.Bottom Line: Yellow bell peppers are an excellent source of vitamin C. One large bell pepper provides almost 600% of the recommended daily amount, which is up to 4 times the amount found in oranges.

8. Cod Liver Oil

Vitamin D deficiency is one of the most common nutrient deficiencies in the world.

This is because the dietary sources of vitamin D are sparse. They include mainly fatty fish and fish liver oils, as well as egg yolks and mushrooms, to a lesser extent.

Vitamin D is essential for bone health. It is also a crucial part of many bodily processes, including immune system function and cancer prevention.

Cod liver oil is a great addition to any diet, especially for people who live far from the equator, where no vitamin D can be synthesized in the skin during the winter months.

Only one tablespoon, or 14 g, of cod liver oil provides 2–3 grams of omega 3 fats and 1400 IU of vitamin D. This is more than 200% of the RDI for vitamin D.

However, cod liver oil also contains high amounts of vitamin A, about 270% of the RDI. Vitamin A can be harmful in excessive amounts, so it is not recommended that adults use more than 1-2 tablespoons per day of cod liver oil.Bottom Line: Cod liver oil is an excellent source of omega-3 fatty acids, vitamin D and vitamin A. Taking more than 1-2 tablespoons per day is not recommended.

Take Home Message

Although multivitamins may be beneficial for some people, they are unnecessary for most. In some cases, they may even provide excessive amounts of certain nutrients.

If you want to boost your nutrient intake, consider adding some of these super nutritious foods to your diet instead of taking a synthetic multivitamin.